Advances in Catalytic Hydrogenation of Oil with Novel Catalytic Systems

Traditionally, nickel-based catalysts (e.g., Raney Ni or Ni/AlO) have been used due to their low cost and high activity. However, Ni catalysts tend to yield excessive saturation and trans-fat isomers, which are undesirable for health. In recent years, intensive research has focused on new catalytic systems to improve selectivity, activity, and environmental performance. This review briefly surveys conventional catalysts and then focuses on two classes of novel catalysts: advanced supported metal catalysts (including noble metals and promoted Ni catalysts) and bimetallic or alloy catalysts. For each system, the article discusses the hydrogenation mechanism, observed activity and selectivity (particularly toward cis monoenes), catalyst stability and regeneration, as well as industrial scale-up potential and environmental impact (e.g., trans-fat formation, energy requirements). Emerging catalyst-free technologies (e.g., plasma hydrogenation) are also highlighted. The paper concludes with perspectives on designing catalysts that meet food-industry demands (high cis-selectivity, low trans content) while minimizing energy use and harmful by-products.